British Insects: the Families of Lepidoptera

Cossidae

Zeuzeridae.

Adults nocturnal; relatively very long-bodied; medium built (wingspan more
than 8 and less than 15 times the thoracic width) to heavily built (wingspan
less than 8 times the thoracic width). The abdomen conspicuously patterned to
plain. Adultsnot of hymenopterous appearance; wings in repose
packed with the forewings directed backwards to cover hindwings and abdomen.

Antennae very short to of medium length; extending to about 0.18–0.48
times the length of the forewing. Antennae of malesbipectinate, or
lamellate. Ocelli present (rarely), or absent. Maxillary palps much reduced;
1 segmented, or 2 segmented. Labial palps ascending (short to medium); 3
segmented. Proboscis absent.

Wingspan(36–)45–104 mm; 7–10.5 times the
thoracic width. Forewings narrow to broad; 2–2.7 times as long as wide.
The outer and hind margins angled at 110–120 degrees. The outer margin
convexly curved; forewings apically blunt. Hindwings ovate to broadly rounded;
similar in breadth to the forewings; with a rounded apex; the upper surfaces
conspicuously patterned above (spotted, and/or reticulated and indistinctly
lined), or plain; with transverse lines, or with neither discal spot nor
transverse lines (without a clear discal spot); with a frenulum.

Neuration of forewings and hindwings dissimilar. Forewings 13 veined;
with 2 anal veins. The anal veins of the forewings comprising 1b and 1c.
Forewings exhibiting a tubular vein 1c. Vein 1b of the forewings furcate
proximally. The transverse vein complete, or incomplete. Forewingswith an accessory cell. Discal cell of the forewings containing a tubular
media (M) vein (this forked, like that of the hindwings). Hindwings 10
veined; with 3 anal veins. The anal veins of the hindwings comprising 1a, 1b and
1c. Hindwings exhibiting vein 1a; exhibiting a tubular vein 1c. Vein 1b of the
hindwings furcate proximally to simple. The transverse vein complete. 6 veins
arising from the hindwing cell. The cell-derived hindwing veins all arising
independently of one another, or 6+7 proximally joined. Vein 8 of the hindwings
completely independent of the cell; not approximating to vein 7.

Fore-legs with a tibial epiphysis. Tibiae of middle legs without spurs, or
2-spurred. Posterior tibiae without spurs, or 4-spurred.

Eggs, larvae and pupae. Eggs not
flattened; smooth or minutely pitted. Larval prolegs 10. Larvae concealed
feeders; wood- or stem- boring. Feeding in stems of grasses and the wood
of various deciduous trees.

Pupae concealed; in stems, or in wood (in the larval galleries). Empty pupae
protruded from place of concealment.

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